1. Technical Field
This device relates to truck ladders specifically ladders that are used to provide access to the truck trailer bed. Such trailer beds are located a substantial distance from the ground making access difficult without the aid of some sort of ladder. Many times truck drivers use makeshift ladders that they carry along with them that are used in all types of weather to climb up to the trailer bed. Such ladders are unstable and inherently unsafe accounting for many accidental injuries and falls.
2. Description of Prior Art
Prior art devices of this type have been developed to address the safety and ease of access issue by providing a number of portable and permanent ladder assemblies for use on truck trailers, see for example U.S. Pat. Nos. 4,139,078, 4,205,862, 5,024,292, 5,046,582, and 5,964,317. In U.S. Pat. No. 4,139,078 a ladder assembly is disclosed for use on a truck trailer having a rail and rung ladder with which is split in guide tracks up under the trailer and held by an elastic retaining strap when not in use.
U.S. Pat. No. 4,205,862 is directed to a truck ladder having a folding three rung portion that pivotally extends down from a support and mounting frame secured to the truck bed.
U.S. Pat. No. 5,024,292 illustrates a portable ladder assembly for truck trailers with mounting sleeves secured to the trailer into which telescopically extensible rail members are selectively secured, rungs extend between the rails and a ladder extension optionally extends there from.
U.S. Pat. No. 5,046,582 claims a portable ladder for truck cargo carrier assemblies in which multiple rung ladder portions pivotally extend from a hand rail portion which in turn is pivotally secured to the cargo opening of a truck trailer.
U.S. Pat. No. 5,964,317 shows a portable ladder for truck trailers having a single center rail with staggered oppositely disposed steps extending there from. A mounting bracket is selectively secured on the trailer bed surface with a central rail post secured thereto. The upper portion of the rail post that extends above the trailer surface acts as a hand rail of sorts.
Other prior art can be seen in Exhibit A in which a Chevron brand retractable ladder for tow trucks is shown having a pivotal adjustment ladder assembly.
In prior art Exhibit B a Pro Step Trucker brand ladder assembly is shown on the web page printout having a fixed open rail ladder which is hooked over the support edge of a truck trailer. A pair of ladder hand railing pivots to extend to an upstanding position.